An endoscope is a long, thin instrument used in medical procedures to view or operate inside a patient's body with minimal intrusiveness. Rather than opening a large cavity to reach a location in a patient's body, a doctor can create a small opening and reach the location by inserting and guiding the endoscope. To view inside a body, the distal end of the endoscope is mounted with a camera lens that transmits a video image of the surrounding tissue. The lens is often cut at an angle to yield an image of the tissue that is more or less (depending on the angle) to the side of, rather than directly in front of, the end of the endoscope.
Endoscopes can be rigid or flexible. A rigid endoscope is in the form of a long, thin tube connected to a base joint, which in turn is typically mounted on a handle. A flexible endoscope is in the form of a long, thin cable. The present invention is for use with rigid endoscopes.
A rigid endoscope is usually fitted with a sleeve: a hollow, rigid tube into which the endoscope is inserted, of a length slightly less than that of the endoscope. The shorter length of the sleeve permits the distal end of the endoscope to protrude slightly from the distal end of the sleeve, thus enabling the imaging or other function of the endoscope. Particularly when the endoscope has an angled lens for viewing sideways, the sleeve may end in an angled cut or an irregular cutaway shape to cover the endoscope as much as possible while permitting the lens to view its object. Prior sleeves connect to the endoscope at the proximal end (i.e., the end nearer to the base joint) and are immovably fixed in relation to the endoscope.
An endoscope sleeve may perform various purposes. One purpose is to protect the endoscope as it is pushed, pulled, and angled within a patient. Another purpose is to introduce irrigation or suction to the area surrounding the distal end, thus either flushing the area with an externally supplied fluid or removing internal matter from the area. For either purpose, the inner diameter of the sleeve is of sufficiently greater diameter than the outer diameter of the endoscope to form a space, or channel, between the two tubes. Irrigation or suction is introduced through that space or channel.
Another purpose of an endoscope sleeve can be to spread bodily tissue away from the distal end of the endoscope, thus clearing a space for the imaging or other function. To this end, the distal end of the sleeve may terminate in a flared tip that angles outwardly from the tubular sleeve. The flared tip pushes or lifts tissue away from the axis of the sleeved endoscope, sheltering the distal end of the endoscope in an umbrella-like space.
Prior sleeves for rigid endoscopes pose several problems for their users. First, the sleeves are sometimes difficult to stabilize in the area to be viewed or treated. Instability compromises the quality and accuracy of the imaging or other function being performed. It is sometimes possible to anchor the endoscope sleeve on nearby tissue; because the endoscope is fixed to the sleeve, the endoscope is stabilized. But such a technique depends on coincidence. Anchoring the sleeve in a convenient spot will not necessarily leave the distal end of the endoscope in its required location.
Second, even if the sleeve could be anchored in a spot that placed the distal end of the endoscope in a favorable position, it would usually be necessary to move the endoscope in various directions--pushing, pulling, rotating, angling--with the result that the anchoring spot for the sleeve would soon be lost. The sleeve simply cannot remain anchored while the endoscope is moved, because the two are fixed relative to one another.
Third, an endoscope fixed to a sleeve is bulkier than an endoscope alone, which limits the spaces into which the endoscope may reach. This is of particular concern where the instrument must pass through a small opening in solid material like bone.
It is therefore an object of this invention to provide an endoscope sleeve that facilitates stabilization of an endoscope to which the sleeve is attached.
It is another object of this invention to provide an endoscope sleeve that permits axial and rotational movement of the endoscope relative to the sleeve.
It is a further object of this invention to provide an endoscope sleeve that can be fixed to an endoscope selectively along the endoscope's length and circumference.
It is yet another object of this invention to provide an endoscope sleeve that operates as an effective anchor when positioned against a stable surface.
It is still another object of this invention to provide an endoscope sleeve that permits extension of the distal end of the endoscope substantially beyond the distal end of the sleeve, thus facilitating the examination of spaces unreachable by a combined endoscope and sleeve.